20.8.4 Peripheral Clock Control

PCHCTRLm controls the settings of Peripheral Channel number m (m=0..38).

Refer to the Table for finding out the m value corresponding to each module input clock(s).

Table 20-12. Register Bit Attribute Legend
SymbolDescriptionSymbolDescriptionSymbolDescription
RReadable bitHCCleared by Hardware(Grey cell)Unimplemented
WWritable bitHSSet by HardwareXBit is unknown at Reset
KWrite to clearSSoftware settable bit——
Name: PCHCTRL
Offset: 0x80
Reset: 0x00000000
Property: RW

Bit 3130292827262524 
          
Access  
Reset  
Bit 2322212019181716 
          
Access  
Reset  
Bit 15141312111098 
          
Access  
Reset  
Bit 76543210 
 WRTLOCKCHEN  GEN[3:0] 
Access RWRWRWRWRWRW 
Reset 000000 

Bit 7 – WRTLOCK Write Lock

After this bit is set to '1', further writes to the PCHCTRLm register will be discarded. The control register of the corresponding Generator n (GENCTRLn), as assigned in PCHCTRLm.GEN, will also be locked. It can only be unlocked by a Power Reset.

Note that Generator 0 cannot be locked.

ValueDescription
0The Peripheral Channel register and the associated Generator register are not locked
1The Peripheral Channel register and the associated Generator register are locked

Bit 6 – CHEN Channel Enable

This bit is used to enable and disable a Peripheral Channel.

ValueDescription
0The Peripheral Channel is disabled
1The Peripheral Channel is enabled

Bits 3:0 – GEN[3:0] Generic Clock Generator

This bit field selects the Generator to be used as the source of a peripheral clock, as shown in the table below:

Table 20-13. Generator Selection
ValueDescription
0x0Generic Clock Generator 0
0x1Generic Clock Generator 1
0x2Generic Clock Generator 2
0x3Generic Clock Generator 3
0x4Generic Clock Generator 4
0x5Generic Clock Generator 5
0x6Generic Clock Generator 6
0x7Generic Clock Generator 7
0x8Generic Clock Generator 8
0x9Generic Clock Generator 9
0xAGeneric Clock Generator 10
0xBGeneric Clock Generator 11
0xC - 0xFReserved
Table 20-14. Reset Value after a User Reset or a Power Reset
ResetPCHCTRLm.GENPCHCTRLm.CHENPCHCTRLm.WRTLOCK
Power Reset0x00x00x0
User Reset0x00x00x0

A Power Reset will reset all the PCHCTRLm registers.

A User Reset will reset a PCHCTRL if WRTLOCK=0, or else the content of that PCHCTRL remains unchanged.

The PCHCTRL register Reset values are shown in the table below, PCHCTRLm Mapping.

ValueNameDescription
0x0GCLK0Generic clock generator 0
0x1GCLK1Generic clock generator 1
0x2GCLK2Generic clock generator 2
0x3GCLK3Generic clock generator 3
0x4GCLK4Generic clock generator 4
0x5GCLK5Generic clock generator 5
0x6GCLK6Generic clock generator 6
0x7GCLK7Generic clock generator 7
0x8GCLK8Generic clock generator 8
0x9GCLK9Generic clock generator 9
0xAGCLK10Generic clock generator 10
0xBGCLK11Generic clock generator 11
0xCGCLK12Generic clock generator 12
0xDGCLK13Generic clock generator 13
0xEGCLK14Generic clock generator 14
0xFGCLK15Generic clock generator 15